(a) Electric haulage by trolley locomotive is not permitted in any gassy mine except on intake air. Where the main intake of fresh air is drawn in through surface openings of old workings, it shall be deemed to come within the definition of “intake air” of article I, section 103(12).¹

(b) It shall be unlawful in any gassy mine to run or operate a locomotive, fed directly or indirectly from a trolley wire, beyond the open entrances to worked out places wherein the pillars have been removed.

(c) In a gassy mine explosion-tested, cable-reel locomotives shall be equipped with two conductor trailing cables.²

(d) No open type electric locomotive or open type electric machine of whatsoever name shall be taken into a working place or places in a gassy mine unless such open type electric locomotives or open type electric machines are operated on intake air. Return airways (or passageways) shall not be used as haulageways for electric locomotives operated from a trolley wire in gassy mines: Provided, however, That if at any time after the effective date of this act a mine classed as non-gassy should be declared gassy under the provisions of this act, the operator of such mine shall, within the six months immediately following such reclassification, discontinue the use of open type electric locomotives or open type electric machines of any kind in a working place or places in such gassy mine or portion thereof. Upon written request from the operator of any such mine the secretary, after investigation, shall have authority to grant an additional six month period to such operator to discontinue the use of such locomotives or machines.